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Tourism Traffic Demand Prediction Using Google Trends Based on EEMD-DBN 被引量:4
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作者 Yi Xiao Xueting Tian +2 位作者 John J. Liu Gaohui Cao Qingxing Dong 《Engineering(科研)》 2020年第3期194-215,共22页
Predicting tourism traffic demand accurately plays an important role in making effective policies for tourist administration. It helps to distribute the resources reasonably and avoid the tourism congestions. This pap... Predicting tourism traffic demand accurately plays an important role in making effective policies for tourist administration. It helps to distribute the resources reasonably and avoid the tourism congestions. This paper considered the noise interference and proposed a hybrid model, combining ensemble empirical mode decomposition (EEMD), deep belief network (DBN) and Google trends, for tourism traffic demand prediction. This model firstly applied dislocation weighted synthesis method to combine Google trends into a search composite index, and then it denoised the series with EEMD. EEMD extracted the high frequency noise from the original series. The low frequency series of search composite index would be used to forecast the low frequency tourism traffic series. Taking the inbound tourism in Shanghai as an example, this paper trained the model and predicted the next 12 months tourism arrivals. The conclusion demonstrated that the forecast error of EEMD-DBN model is lower remarkably than the baselines of ARIMA, GM(1,1), FTS, SVM, CES and DBN model. This revealed that nosing processing is necessary and EEMD-DBN forecast model can improve the prediction accuracy. 展开更多
关键词 TOURISM Traffic demand Forecasting DEEP Learning GOOGLE TRENDS Composite Search Index Ensemble Empirical Mode Decomposition (EEMD) DEEP BELIEF Network (DBN)
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Multi-Step Clustering of Smart Meters Time Series:Application to Demand Flexibility Characterization of SME Customers
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作者 Santiago Bañales Raquel Dormido Natividad Duro 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期869-907,共39页
Customer segmentation according to load-shape profiles using smart meter data is an increasingly important application to vital the planning and operation of energy systems and to enable citizens’participation in the... Customer segmentation according to load-shape profiles using smart meter data is an increasingly important application to vital the planning and operation of energy systems and to enable citizens’participation in the energy transition.This study proposes an innovative multi-step clustering procedure to segment customers based on load-shape patterns at the daily and intra-daily time horizons.Smart meter data is split between daily and hourly normalized time series to assess monthly,weekly,daily,and hourly seasonality patterns separately.The dimensionality reduction implicit in the splitting allows a direct approach to clustering raw daily energy time series data.The intraday clustering procedure sequentially identifies representative hourly day-unit profiles for each customer and the entire population.For the first time,a step function approach is applied to reduce time series dimensionality.Customer attributes embedded in surveys are employed to build external clustering validation metrics using Cramer’s V correlation factors and to identify statistically significant determinants of load-shape in energy usage.In addition,a time series features engineering approach is used to extract 16 relevant demand flexibility indicators that characterize customers and corresponding clusters along four different axes:available Energy(E),Temporal patterns(T),Consistency(C),and Variability(V).The methodology is implemented on a real-world electricity consumption dataset of 325 Small and Medium-sized Enterprise(SME)customers,identifying 4 daily and 6 hourly easy-to-interpret,well-defined clusters.The application of the methodology includes selecting key parameters via grid search and a thorough comparison of clustering distances and methods to ensure the robustness of the results.Further research can test the scalability of the methodology to larger datasets from various customer segments(households and large commercial)and locations with different weather and socioeconomic conditions. 展开更多
关键词 Electric load clustering load profiling smart meters machine learning data mining demand flexibility demand response
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Seismic displacement demand prediction in non-linear domain: Optimization of the N2 method
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作者 Lorenzo Diana Andrea Manno Pierino Lestuzzi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第1期141-158,共18页
In Europe, computation of displacement demand for seismic assessment of existing buildings is essentially based on a simplified formulation of the N2 method as prescribed by Eurocode 8(EC8). However, a lack of accurac... In Europe, computation of displacement demand for seismic assessment of existing buildings is essentially based on a simplified formulation of the N2 method as prescribed by Eurocode 8(EC8). However, a lack of accuracy of the N2 method in certain conditions has been pointed out by several studies. This paper addresses the assessment of effectiveness of the N2 method in seismic displacement demand determination in non-linear domain. The objective of this work is to investigate the accuracy of the N2 method through comparison with displacement demands computed using non-linear timehistory analysis(NLTHA). Results show that the original N2 method may lead to overestimation or underestimation of displacement demand predictions. This may affect results of mechanical model-based assessment of seismic vulnerability at an urban scale. Hence, the second part of this paper addresses an improvement of the N2 method formula by empirical evaluation of NLTHA results based on EC8 ground-classes. This task is formulated as a mathematical programming problem in which coefficients are obtained by minimizing the overall discrepancy between NLTHA and modified formula results. Various settings of the mathematical programming problem have been solved using a global optimization metaheuristic. An extensive comparison between the original N2 method formulation and optimized formulae highlights benefits of the strategy. 展开更多
关键词 N2 METHOD SEISMIC vulnerability assessment NON-LINEAR time-history analysis spectrum compatible recordings DISPLACEMENT demand determination OPTIMIZATION strength reduction factor
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An Ordering Policy for Deteriorating Items with Time-Dependent Quadratic Demand and Salvage Value under Permissible Delay in Payment 被引量:1
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作者 Trailokyanath Singh Madan Mohan Muduly +2 位作者 Chittaranjan Mallick Rahul Kumar Gupta Hadibandhu Pattanayak 《American Journal of Operations Research》 2019年第5期201-218,共18页
The article deals with an economic order quantity (EOQ) inventory model for deteriorating items in which the supplier provides the purchaser a permissible delay in payment. This is so when deterioration of units in th... The article deals with an economic order quantity (EOQ) inventory model for deteriorating items in which the supplier provides the purchaser a permissible delay in payment. This is so when deterioration of units in the inventory is subject to constant deterioration rate, demand rate is quadratic function of time and salvage value is associated with the deteriorated units. Shortages in the system are not allowed to occur. A mathematical formulation is developed when the supplier offers a permissible delay period to the customers under two circumstances: 1) when delay period is less than the cycle of time;and 2) when delay period is greater than the cycle of time. The method is suitable for the items like state-of-the-art aircrafts, super computers, laptops, android mobiles, seasonal items and machines and their spare parts. A solution procedure algorithm is given for finding the optimal order quantity which minimizes the total cost of an inventory system. The article includes numerical examples to support the effectiveness of the developed model. Finally, sensitivity analysis on some parameters on optimal solution is provided. 展开更多
关键词 Constant Deterioration RATE Deteriorating Items Economic Order Quantity Permissible Delay in PAYMENT SALVAGE Value TIME-DEPENDENT QUADRATIC demand RATE
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Intelligent Load Management Scheme for a Residential Community in Smart Grids Network Using Fair Emergency Demand Response Programs
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作者 Muhammad Ali Z.A. Zaidi +3 位作者 Qamar Zia Kamal Haider Amjad Ullah Muhammad Asif 《Energy and Power Engineering》 2012年第5期339-348,共10页
In the framework of liberalized deregulated electricity market, dynamic competitive environment exists between wholesale and retail dealers for energy supplying and management. Smart Grids topology in form of energy m... In the framework of liberalized deregulated electricity market, dynamic competitive environment exists between wholesale and retail dealers for energy supplying and management. Smart Grids topology in form of energy management has forced power supplying agencies to become globally competitive. Demand Response (DR) Programs in context with smart energy network have influenced prosumers and consumers towards it. In this paper Fair Emergency Demand Response Program (FEDRP) is integrated for managing the loads intelligently by using the platform of Smart Grids for Residential Setup. The paper also provides detailed modelling and analysis of respective demands of residential consumers in relation with economic load model for FEDRP. Due to increased customer’s partaking in this program the load on the utility is reduced and managed intelligently during emergency hours by providing fair and attractive incentives to residential clients, thus shifting peak load to off peak hours. The numerical and graphical results are matched for intelligent load management scenario. 展开更多
关键词 demand RESPONSE (DR) FAIR EMERGENCY demand RESPONSE Program (FEDRP) Intelligent Load Management (ILM) RESIDENTIAL Area Networks (RAN) Smart Grids
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Battery Energy Storage System and Demand Response Based Optimal Virtual Power Plant Operation
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作者 Ya-Chin Chang Rung-Fang Chang 《Journal of Applied Mathematics and Physics》 2017年第4期766-773,共8页
With certain controllability of various distribution energy resources (DERs) such as battery energy storage system (BESS), demand response (DR) and distributed generations (DGs), virtual power plant (VPP) can suitably... With certain controllability of various distribution energy resources (DERs) such as battery energy storage system (BESS), demand response (DR) and distributed generations (DGs), virtual power plant (VPP) can suitably regulate the powers access to the distribution network. In this paper, an optimal VPP operating problem is used to optimize the charging/discharging schedule of each BESS and the DR scheme with the objective to maximize the benefit by regulating the supplied powers over daily 24 hours. The proposed solution method is composed of an iterative dynamic programming optimal BESS schedule approach and a particle swarm optimization based (PSO-based) DR scheme approach. The two approaches are executed alternatively until the minimum elec-tricity cost of the whole day is obtained. The validity of the proposed method was confirmed with the obviously decreased supplied powers in the peak-load hours and the largely reduced electricity cost. 展开更多
关键词 Battery ENERGY Storage System Distributed ENERGY RESOURCE demand Response ITERATIVE Dynamic PROGRAMMING Particle SWARM Optimization Virtual Power Plant
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Renal cell carcinoma: Evolving and emerging subtypes 被引量:7
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作者 Suzanne M Crumley Mukul Divatia +3 位作者 Luan Truong Steven Shen Alberto G Ayala Jae Y Ro 《World Journal of Clinical Cases》 SCIE 2013年第9期262-275,共14页
Our knowledge of renal cell carcinoma(RCC) is rapidly expanding. For those who diagnose and treat RCC, it is important to understand the new developments. In recent years, many new renal tumors have been described and... Our knowledge of renal cell carcinoma(RCC) is rapidly expanding. For those who diagnose and treat RCC, it is important to understand the new developments. In recent years, many new renal tumors have been described and defined, and our understanding of the biology and clinical correlates of these tumors is changing. Evolving concepts in Xp11 translocation carcinoma, mucinous tubular and spindle cell carcinoma, multilocular cystic clear cell RCC, and carcinoma associated with neuroblastoma are addressed within this review. Tubulocystic carcinoma, thyroid-like follicular carcinoma of kidney, acquired cystic disease-associated RCC, and clear cell papillary RCC are also described. Finally, candidate entities, including RCC with t(6;11) translocation, hybrid oncocytoma/chromophobe RCC, hereditary leiomyomatosis and RCC syndrome, and renal angiomyoadenomatous tumor are reviewed. Knowledge of these new entities is important for diagnosis, treatment and subsequent prognosis. This review provides a targeted summary of new developments in RCC. 展开更多
关键词 RENAL CELL CARCINOMA SUBTYPES Xp11 TRANSLOCATION Mucinous tubular and spindle CELL Multilocular CYSTIC clear CELL CARCINOMA associated with neuroblastoma recently described entities Clear CELL papillary RENAL CELL CARCINOMA Acquired CYSTIC kidney disease Hereditary leiomyomatosis Candidate entities RENAL CELL CARCINOMA with t(6 11)translocation
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黄土丘陵小流域植被生态用水评价 被引量:25
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作者 黄奕龙 陈利顶 +2 位作者 傅伯杰 张利萍 王仰麟 《水土保持学报》 CSCD 北大核心 2005年第2期152-155,194,共5页
以黄土丘陵区安家沟小流域为例,计算了植被最小需水量,评价了不同植被类型的生态用水量。研究结果表明:(1)土壤含水量、蒸散量均与植被类型和降雨量密切相关。对于相同年份,乔灌林地的土壤含水量和蒸散量都显著地大于农地;对于相同的植... 以黄土丘陵区安家沟小流域为例,计算了植被最小需水量,评价了不同植被类型的生态用水量。研究结果表明:(1)土壤含水量、蒸散量均与植被类型和降雨量密切相关。对于相同年份,乔灌林地的土壤含水量和蒸散量都显著地大于农地;对于相同的植被类型,干旱年份(2 0 0 2年)的土壤含水量和蒸散量都显著小于湿润年份(2 0 0 3年)。(2 )从月尺度来说,不论是干旱年还是湿润年,植被生态用水在生长季节旺季均低于其最小生态需水量;从年尺度来说,干旱年份所有植被生态用水均低于其最小生态需水量,但湿润年份所有植被(除小麦外)生态用水都可以达到其最小生态需水量;以多年平均降雨量为标准,马铃薯和沙棘可以达到其最小生态需水标准,其它4种植被类型都不能达到其最小生态需水标准。本文建议:对于半干旱黄土丘陵地区,植被恢复不宜以乔灌林为主,并注意斑块形状和种植密度;在植被恢复的过程中,可以采用人工方法,促进自然恢复。 展开更多
关键词 2003 2002 湿
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Demand and Response in Smart Grids for Modern Power System
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作者 Muhammad Qamar Raza Muhammad Usman Haider +2 位作者 S. Muhammad Ali Muhammad Zeeshan Rashid Farooq Sharif 《Smart Grid and Renewable Energy》 2013年第2期133-136,共4页
Micro-grid plays a vital role in fulfilling the increasing demand by using distributed renewable energy resources. Demand and response technique can be broadly classified under the setup DR deployed (e.g. ISO’s/RTO’... Micro-grid plays a vital role in fulfilling the increasing demand by using distributed renewable energy resources. Demand and response technique can be broadly classified under the setup DR deployed (e.g. ISO’s/RTO’s). Demand response program can be implemented to improve power system quality, reliability and increasing demand. In modern power industry, strategic player can take more benefit from more emphasized DR study in terms of social benefit (uninterrupted power supply to consumers) and economy. This paper proposes the distributed micro-grid control and implemented control setup implemented demand response algorithm, which provides better power system reliability. This paper presents contingencies control demand and response for micro-grid. The main advantage of implementation of demand and response algorithms in Micro-grids provides reliable power supplies to consumers. The proposed micro-grid TCP/IP setup provides a chance to respond the contingencies to recover the shed to active condition. Micro-grid controller implements demand and response algorithm reasonable for managing the demand of the load and intelligent load scheme in case of blackout. 展开更多
关键词 demand RESPONSE (DR) Micro-Grid (MG) POWER SYSTEM Reliability Distributed Generation (DG) Renewable Energy Resources (RER) POWER SYSTEM CONTINGENCIES
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Demand Elasticity for China's Major Imported Agriculture Textile Material Based on Restricted Version of Source Differentiated Almost Ideal Demand System Model
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作者 TIAN Congying XIAO Haifeng 《Journal of Donghua University(English Edition)》 EI CAS 2018年第4期326-332,共7页
By comparing China's import of major imported agriculture textile material( cotton and wool),the characteristics of import are concluded. On this basis,a restricted version of source differentiated almost ideal de... By comparing China's import of major imported agriculture textile material( cotton and wool),the characteristics of import are concluded. On this basis,a restricted version of source differentiated almost ideal demand system( RSDAIDS) is used to estimate the income and price elasticity of major imported agriculture textile material from the major sources based on the data from 1992 to 2015. The results are shown as follows.( 1) Although the dependency on imported cotton is lower than wool, the fluctuation of cotton import is much more drastic; China's demand for cotton is relatively price elastic with higher expenditure elasticity compared with wool; besides,the existence of complementarity is proved between imported cotton and wool.( 2) According to the import elasticity of cotton,demand for cotton imported from India shows priority over cotton from other sources; demand for cotton imported from America is the most price-sensitive one; substitution among cotton from different sources is weak.( 3) According to the import elasticity of wool,wool imported from Uruguay has bright market prospects. In addition,wool imported from Australia has irreplaceable advantage than that from New Zealand. 展开更多
关键词 AGRICULTURE TEXTILE MATERIAL retricted VERSION of sourcedifferentiated almost ideal demand system (RSDA1DS) MODEL importdemand estimation
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Probabilistic estimate of rock mass static and dynamic demands for underground excavation stabilisation 被引量:1
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作者 Ernesto Villaescusa Alan Thompson Christopher Windsor 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2019年第3期481-493,共13页
Excavation damage under high in situ stress depends largely upon the potential block size associated with any violent ejection.The size and shape of the dynamic instability are largely controlled by the location,orien... Excavation damage under high in situ stress depends largely upon the potential block size associated with any violent ejection.The size and shape of the dynamic instability are largely controlled by the location,orientation and extent of the pre-existing geological discontinuities.A new methodology is presented in which the rock mass demand can be expressed in terms of the mass in tonnes of unstable rock that is ejected per unit area of the excavation surface where failure occurs.A probabilistic approach has been implemented to estimate the potential rock mass instabilities and their associated static and dynamic demands.The new methodology considers that the strain energy released by the rock mass during violent stress-driven failure is largely converted into kinetic energy of ejection for blocks.The estimated dynamic demand has been favourably compared with observations of rock mass damage in a number of underground excavations. 展开更多
关键词 GEOLOGICAL structures PROBABILISTIC design UNDERGROUND EXCAVATIONS High stresses Dynamic and static demandS Deep mining
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基于农作物需求的中国化肥资源供求平衡研究(Ⅰ)——中国氮肥资源 被引量:6
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作者 刘爱民 封志明 于格 《资源科学》 CSSCI CSCD 北大核心 2005年第3期41-46,共6页
化肥是一种重要的农业资源,氮肥是最重要的化肥资源品种。供给和需求是化肥资源供求动态平衡的两个方面,影响供给的主要因素有国内生产和进出口;影响需求的主要因素有不同地区农作物类型、不同农作物的种植面积和不同农作物对不同化肥... 化肥是一种重要的农业资源,氮肥是最重要的化肥资源品种。供给和需求是化肥资源供求动态平衡的两个方面,影响供给的主要因素有国内生产和进出口;影响需求的主要因素有不同地区农作物类型、不同农作物的种植面积和不同农作物对不同化肥品种的施用量。本文在分析影响化肥供求平衡因素的基础上,对尿素和碳铵等主要氮肥品种的供求平衡问题进行了重点研究,并建立了分省的尿素供求平衡表。研究结果显示,尿素的氮肥供给量占中国氮肥供给总量的55.0%左右;而碳铵的氮肥供给量占中国氮肥供给总量的比例已有1995年的38.7%,下降到2003年的23.0%左右。另外,单一氮肥品种的氮肥供给量占氮肥供给总量的比例由1995年的96.2%,减少到2003年的87.0%。目前我国尿素供过于求,而碳铵供求基本平衡。 展开更多
关键词 1995 2003 尿
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21世纪人才素质需求与高校体育教育改革新特点 被引量:2
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作者 李亚俊 《怀化学院学报》 2005年第2期142-144,共3页
采用数理统计法、资料分析对比法,对富有知识经济特点“雏形”的部分企业集团、公司40岁以下工程师类科技人才现阶段素质需求情况进行调查研究分析,认为知识经济时代的高级专门人才对素质的需求具有新的七大特征:第一,连续工作能力和较... 采用数理统计法、资料分析对比法,对富有知识经济特点“雏形”的部分企业集团、公司40岁以下工程师类科技人才现阶段素质需求情况进行调查研究分析,认为知识经济时代的高级专门人才对素质的需求具有新的七大特征:第一,连续工作能力和较快的恢复能力;第二,持续保持高度集中注意力的能力和敏锐的观察、反应能力;第三,良好的职业道德和协作精神;第四,良好的心理耐挫能力;第五,良好的竞争意识;第六,善于学习和创新能力;第七,对小肌肉群的控制能力.针对现行我国高校体育教育忽视主要体质需求、忽视“失败”体育教育、忽视个性发展等不足,提出了6点改革建议. 展开更多
关键词 21
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基于LabVIEW 7.0 Express的测定化学电池E-t关系的虚拟仪器 被引量:2
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作者 李元文 李将渊 +3 位作者 王文彬 刘赵荣 蔡铎昌 唐自龙 《西华师范大学学报(自然科学版)》 2005年第2期205-208,共4页
研制了基于LabVIEW7.0Express的实时测定电池电动势(E)与温度(t)关系的化学虚拟仪器系统.运用集成运放器设计制作了电池电动势和温度的调理电路,通过PCI2002卡双通道同时采集,实现了E随t变化关系的跟踪测定,计算机实时绘出E-t曲线.用Lab... 研制了基于LabVIEW7.0Express的实时测定电池电动势(E)与温度(t)关系的化学虚拟仪器系统.运用集成运放器设计制作了电池电动势和温度的调理电路,通过PCI2002卡双通道同时采集,实现了E随t变化关系的跟踪测定,计算机实时绘出E-t曲线.用LabVIEWFunction模板中的相关函数编程,剔除野值,获得最佳拟合E-t函数表达式.应用结果表明:该系统操作简单、界面友好,实时数据显示和自动处理数据,避免了人工操作和数据处理的人为误差,结果令人满意. 展开更多
关键词 LABVIEW EXPRESS
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浙江省普通高校本、专科大学生学习需要调查与对比研究 被引量:5
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作者 廖传景 《现代大学教育》 北大核心 2005年第2期64-68,共5页
本文就当前在校大学生的学习需要进行了问卷调查,经过数据汇总和比较分析,发现有以下7类特点:(1)本、专科生都以学习为自身第一需要,但在对学习等问题的看法上出现了显著性差异;(2 )自身发展与专业前途受到本、专科大学生的关注,对恋爱... 本文就当前在校大学生的学习需要进行了问卷调查,经过数据汇总和比较分析,发现有以下7类特点:(1)本、专科生都以学习为自身第一需要,但在对学习等问题的看法上出现了显著性差异;(2 )自身发展与专业前途受到本、专科大学生的关注,对恋爱、学习成绩和专业前途表现出显著性差异;(3)无论本科还是专科大学生都确立了正确的努力方向,但专科学生表现出更强的矛盾性;(4)学习动力来自职业要求和家庭、社会期望;(5 )希望与教师建立真诚互动的关系;(6 )消遣、娱乐类书籍成为学生阅读书目的首选;(7)在专业外学习目标设计上呈现多元、分化的特点。针对在校本、专科大学生身上所表现出来的学习需要及特点,应明确把握,并施以针对性的教育,采取相应的对策。 展开更多
关键词
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基于自忆性原理和EMD的中国清洁能源需求组合预测 被引量:1
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作者 汪哲荪 袁潇晨 +2 位作者 魏一鸣 金菊良 焦建玲 《水电能源科学》 北大核心 2010年第9期171-174,170,共5页
以中国历年能源消费量为基础,分别建立灰色自忆性预测模型和数据机理自忆性预测模型;利用经验模态分解方法分析中国能源消费增长率在经济、人口、城市化下的变化情况,并建立基于经验模态分解的BP神经网络预测模型;通过遗传算法构建能源... 以中国历年能源消费量为基础,分别建立灰色自忆性预测模型和数据机理自忆性预测模型;利用经验模态分解方法分析中国能源消费增长率在经济、人口、城市化下的变化情况,并建立基于经验模态分解的BP神经网络预测模型;通过遗传算法构建能源需求总量组合预测模型,求得中国清洁能源需求总量.研究结果表明:组合预测能够充分利用多个模型的丰富信息,提高预测的准确性;2020年中国清洁能源需求量将达到5.02×108~8.26×108 tce,应优先开发清洁能源. 展开更多
关键词 EMD Empirical Mode Decomposition Based China Energy demand CLEAN
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南水北调西线一期工程调水地区河道内生态环境需水的分析与计量 被引量:16
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作者 张玫 贾新平 魏洪涛 《资源科学》 CSSCI CSCD 北大核心 2005年第4期180-184,共5页
南水北调西线一期工程规划从长江上游雅砻江、大渡河的5条支流调水入黄河,总调水量40×108m3。如此大规模的引水是否会对原来河流的功能特别是引水坝址附近生态环境功能造成不利影响?针对该问题,本文在分析调水地区径流特征的基础上... 南水北调西线一期工程规划从长江上游雅砻江、大渡河的5条支流调水入黄河,总调水量40×108m3。如此大规模的引水是否会对原来河流的功能特别是引水坝址附近生态环境功能造成不利影响?针对该问题,本文在分析调水地区径流特征的基础上,分别采用7Q10法,Tennant法以及湿周法计算了不同引水坝址下游河道的生态环境低限用水需求,推荐西线一期工程各引水坝址下游河道生态环境低限用水量,除克柯坝址为2m3/s,其余坝址均为5m3/s。并据此分析了南水北调西线一期工程实施后对引水河道生态环境的影响。结果表明调水后各引水河流基本上依旧能够满足其河道内生态环境用水需求,不会损害河流基本的生态环境功能。 展开更多
关键词 西线 湿
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广西北部湾经济区水资源可利用量及承载能力研究 被引量:2
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作者 莫崇勋 蔡德所 +1 位作者 杜群超 孙桂凯 《水力发电》 北大核心 2010年第11期9-12,共4页
通过分析广西北部湾经济区水资源开发状况、可利用量以及人类生存与发展对水资源的需求,采用最大可承载人口数量方法,评估了该地区不同水平年水资源在合理和极限两种开发利用状态下的人口承载量。计算结果表明,在合理开发利用状态下,经... 通过分析广西北部湾经济区水资源开发状况、可利用量以及人类生存与发展对水资源的需求,采用最大可承载人口数量方法,评估了该地区不同水平年水资源在合理和极限两种开发利用状态下的人口承载量。计算结果表明,在合理开发利用状态下,经济区将在2030年出现人口超载77.83万人,而水资源本底条件较差的北海市在2005年~2030年人口超载20万~160万人;在极限开发利用状态下,只有北海市在2010年~2030年人口超载17万~110万人。建议采取跨流域调水、雨洪资源利用等措施,以满足广西北部湾经济区经济社会的可持续发展对水资源的需求。 展开更多
关键词 广西 Beibu GULF Carrying Capacity Water Resources
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艾滋病机遇性胸部感染的X线平片表现 被引量:13
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作者 朱文科 陆普选 +5 位作者 单鸿 余卫业 刘艳 杨根东 刘锦清 臧建 《中国医学影像学杂志》 CSCD 2005年第3期202-205,共4页
目的:提高艾滋病机遇性胸部感染的诊断水平。材料和方法:回顾性分析艾滋病机遇性胸部感染50例的X线胸片及相关临床资料。结果:肺结核2 1例( 4 2 % ) ,片状融合的渗出性病灶1 3例,弥漫性粟粒影6例;胸内淋巴结肿大9例;卡氏肺囊虫肺炎1 6例... 目的:提高艾滋病机遇性胸部感染的诊断水平。材料和方法:回顾性分析艾滋病机遇性胸部感染50例的X线胸片及相关临床资料。结果:肺结核2 1例( 4 2 % ) ,片状融合的渗出性病灶1 3例,弥漫性粟粒影6例;胸内淋巴结肿大9例;卡氏肺囊虫肺炎1 6例( 32 % ) ,双侧肺门及中下肺野可见网状、小点状影,片絮状或斑片状影1 0例,两肺弥漫性或局限性磨玻璃影8例;细菌性感染8例( 1 6 % ) ,片状实变影7例,肺结块影并空洞1例;真菌性感染5例( 1 0 % ) ,弥漫粟粒样小结节影3例,肺门淋巴结肿大1例。结论:艾滋病机遇性胸部感染的X线表现缺乏特征性,诊断须结合临床与实验室检查,并注意发病率较高的肺结核与卡氏肺囊虫肺炎。 展开更多
关键词 X线 X线 X线
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Optimal Scheme with Load Forecasting for Demand Side Management (DSM) in Residential Areas
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作者 Mohamed AboGaleela Magdy El-Marsafawy Mohamed El-Sobki 《Energy and Power Engineering》 2013年第4期889-896,共8页
Utilities around the world have been considering Demand Side Management (DSM) in their strategic planning. The costs of constructing and operating a new capacity generation unit are increasing everyday as well as Tran... Utilities around the world have been considering Demand Side Management (DSM) in their strategic planning. The costs of constructing and operating a new capacity generation unit are increasing everyday as well as Transmission and distribution and land issues for new generation plants, which force the utilities to search for another alternatives without any additional constraints on customers comfort level or quality of delivered product. De can be defined as the selection, planning, and implementation of measures intended to have an influence on the demand or customer-side of the electric meter, either caused directly or stimulated indirectly by the utility. DSM programs are peak clipping, Valley filling, Load shifting, Load building, energy conservation and flexible load shape. The main Target of this paper is to show the relation between DSM and Load Forecasting. Moreover, it highlights on the effect of applying DSM on Forecasted demands and how this affects the planning strategies for utility companies. This target will be clearly illustrated through applying the developed algorithm in this paper on an existing residential compound in Cairo-Egypt. 展开更多
关键词 Component demand Side Management(DSM) LOAD factor(L.F.) Short TERM LOAD Forecatsing(STLF) Long TERM LOAD Forecasting(LTLF) Artificial Neural Network(ANN)
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